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The ameloblastoma is a tumor arising predominantly in the mandible from odontogenic epithelium, and is locally invasive. It is rarely malignant; but even when benign, it causes gross local destruction and expansion of tissue. Growth is persistent, and recurrence may occur more than a decade after presumed total resection. Surgical resection should include a reasonable margin of healthy tissue whenever possible. Late patient presentation due to a paucity of symptoms, and insiduous tumor growth patterns render complete removal of the ameloblastoma difficult. Follow-up examinations should span a prolonged period, exceeding 10-15 years. 相似文献
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996.
Humoral immune aberrations may occur in the cerebrospinal fluid (CSF) of patients with lymphoproliferative and other neoplastic diseases infiltrating the central nervous system (CNS). Such aberrations may be of diagnostic importance. We therefore studied CSF and serum from 47 patients with lymphoproliferative diseases and from 16 patients with various nonlymphoid neoplasias; 17 patients and 12 patients, respectively, had neoplastic CNS involvement. Elevated CSF IgM index and oligoclonal IgG bands in CSF and serum were commonly found, especially in patients with CNS involvement. Cerebrospinal fluid IgG and IgA indexes were usually normal. Increased CSF to serum albumin ratio, reflecting blood-brain barrier dysfunction, and increased CSF beta 2-microglobulin concentration were most common in patients with CNS involvement. The results indicate that neoplastic CNS disease should be borne in mind when CSF humoral immune aberrations are found. 相似文献
997.
The paper is concerned with the results of a study of the circadian rhythm of cortisol secretion and sensitivity of the hypothalamohypophyseal system to small doses of dexamethasone administered in different time of a day to patients with obesity. Disturbance of the circadian rhythm of cortisol secretion resulting in change of the nature of cortisol discharge in the second half of a day, was revealed. Three groups of patients were defined with relation to the type of response of the hypothalamohypophyseal system to dexamethasone administration: with normal, paradoxical and hypersensitive reactions. The results of the study of the circadian rhythm and response of the hypothalamohypophyseal system to dexamethasone were indicative of hypothalamic disturbances in obesity. The authors emphasized the relationship between the nature of sensitivity of the hypothalamohypophyseal system to dexamethasone and age at which the disease developed. 相似文献
998.
D A Eckerman D Segbefia S Manning G S Breese 《Pharmacology, biochemistry, and behavior》1987,27(3):513-515
Rats were trained to press a lever for food pellets provided according to a fixed interval 60-sec schedule of reinforcement. Probe trials (peak trials) assessed responding over two-min periods with no pellet delivered. The low rates of responding found early and late in probe trials were increased by methylphenidate and 1.0 mg/kg d-amphetamine (rate-dependent effect). Further, the mean time of responding (peak time) was shortened for both drugs (timing effect). 相似文献
999.
Twenty-four-hour intragastric acidity and clinical trial of bedtime enprostil 70 μg compared with ranitidine 300 mg in duodenal ulcer 总被引:2,自引:2,他引:0
R. P. WALT R. E. POUNDER C. J. HAWKEY I. A. SANTANA K. W. SOMERVILLE R. F. A. LOGAN R. G. LONG M. J. S. LANGMAN 《Alimentary pharmacology & therapeutics》1987,1(2):161-166
The effects of bedtime 70 micrograms and twice daily 35 micrograms doses of enprostil on 24-hour intragastric acidity were investigated in nine duodenal ulcer patients in remission. Median nocturnal acidity decreased significantly by 30% with 35 micrograms twice daily, and by 48% with 70 micrograms at bedtime. In a clinical trial using bedtime dosing, 102 duodenal ulcer patients randomly received either ranitidine 300 mg or enprostil 70 micrograms. More ulcers healed after 4 and 8 weeks treatment with ranitidine than with enprostil (76% ranitidine vs 52% enprostil, at 4 weeks p = 0.0065 and 94% vs 68%, respectively at 8 weeks, P = 0.0007). However, 6 months after cessation of treatment there was no material difference in overall outcome. Despite combining mucosal protection with acid inhibition enprostil treatment conferred no advantage over simple acid inhibition. 相似文献